This invention relates to horizontal sidewall sprinklers for distributing liquid from a sidewall of an environment which is subject to a fire hazard, and more particularly, relates to a concealed horizontal sidewall sprinkler having a cover.
The Bosio et al. U.S. Pat. No. 5,727,737, the disclosure of which is incorporated herein by reference, discloses a horizontal sidewall sprinkler having a sprinkler body and deflector. The Bosio et al. U.S. Pat. No. 5,687,914, the disclosure of which is incorporated herein by reference, discloses a pendent-type sprinkler suspended in an opening in a ceiling plate and having a cylindrical portion with slots and helically arranged projections between the slots to permit mounting and removal of a cover assembly on a threaded cylindrical wall of a cup mounted on a sprinkler body by axial motion. That patent, as well as the Leininger et al. U.S. Pat. No. 4,880,063, the disclosure of which is incorporated herein by reference, discloses a gap between a cover supported from a cup-shaped member and an adjacent flange of the cup-shaped member. The Polan U.S. Pat. No. 5,097,906 discloses a concealed frame-type ceiling sprinkler arrangement suspended from a ceiling and having a frustoconical cover portion with slots extending along the sidewall of the cover. The Fischer et al. U.S. Pat. No. 5,152,344 discloses a concealed ceiling sprinkler having a cover assembly in which a cover is supported by soldered tabs extending from a flange of a cylindrical member and springs are arranged to urge the cover away from the flange when the solder is melted.
Covers are used with sprinklers mostly for aesthetic reasons. Nonetheless, a concealed horizontal sidewall sprinkler must have a sprinkler cover ejection mechanism that ensures complete and timely ejection of the cover prior to actuation of the sprinkler head and a venting arrangement that ensures proper and timely activation of the sprinkler. Further, a concealed horizontal sidewall sprinkler must have openings in its cover designed so that hot gases can reach the solder holding the cover in place to melt the solder quickly. Moreover, the cover must be ejected and the sprinkler must be actuated regardless of the orientation of the openings in the cover after installation. Finally, for aesthetic purposes, it is desirable to minimize the size of the cover openings.
Accordingly, it is an object of the present invention to provide a concealed horizontal sidewall sprinkler arrangement which overcomes disadvantages of the prior art.
Another object of the invention is to provide a concealed horizontal sprinkler arrangement installed in a sidewall and having a cover which is slidably mountable on a sprinkler.
These and other objects of the invention are attained by providing a concealed horizontal sidewall sprinkler arrangement mounted in a sidewall and having a sprinkler body adapted to be connected to a source of fire extinguishing liquid and a cover supported from the sprinkler body and having slots to permit air circulation. A cover support is mounted substantially concentrically to the sprinkler body and has a threaded cylindrical wall extending away from the source of fire extinguishing liquid. The threaded cylindrical wall engages a sleeve which at one end has a slotted cylindrical portion with helically arranged projections to be received in the threads of the threaded cylindrical wall of the cover support. The other end of the sleeve has a flange with a plurality of tabs extending away from the cylindrical portion. In a preferred embodiment, a cover has a flange portion attached by solder to the tabs extending from the flange of the sleeve and has a projecting portion extending away from the flange portion to accommodate the sprinkler body. The cover also has a plurality of slots and is spaced from the flange of the sleeve by the tabs, forming an annular gap. At least one spring is interposed between the flange and the cover for urging the cover away from the sleeve when the solder fuses at elevated temperatures. In another preferred embodiment, the projecting portion of the cover is frustoconical in shape and the centerline of each slot in the cover extends substantially in a plane extending through the axis of the frustoconically shaped cover.